Sunday, August 28, 2016

Stone-Age Astronomical Instruments: Newgrange & Portuguese Burial Tombs

Stone-Age Scientific & Astronomical Instruments: 
Newgrange & Portuguese Burial Tombs

Scanning the latest science news, as I do everyday, I came across this intriguing headline:
Are 6,000-year-old Stone Burial Tombs The World’s First Astronomy Telescopes? 

The Dolmen of Cerqueira in Portugal showing the long passageway.
"dolmen is a type of single-chamber megalithic tomb, usually consisting of two or more vertical megaliths supporting a large flat horizontal capstone ("table"), although there are also more complex variants. Most date from the early Neolithic (4000–3000 BC)." (

The idea is that passageways in Portuguese burial tombs were designed to enhance the view of a portion of the sky. This made it much easier to see the first appearance of a particular star just before dawn or just after sunset. 
Archaeologists studying 6,000-year-old burial tombs in Portugal believe that the stone edifices could very well be the oldest astronomy telescopes in existence. Researchers from the United Kingdom, noting the alignment of the tombs, think that the passages into the burial chambers may have formed a tunnel-like effect, thus effecting possibly the world’s first ever astronomy telescopes.
After reading a number of articles about these 'prehistoric telescopes', I realized that this idea is very similar to what I proposed over a year ago in this blog about the ability of Neolithic people 5,000 years ago at the Newgrange passage tomb in Ireland. They were able to determine the exact day of the winter solstice with a carefully built passageway that 'trapped' the winter solstice sunlight. 

In both cases the passageways can be thought of as instruments that were designed to enhance a view of the sky so that accurate observations of heavenly bodies could be made. In the case of the Portuguese burial tombs the observation was of stars, in the case of Newgrange, the observation was of the sunrise at the time of the winter solstice.

The following is quoted from the article:
Are 6,000-year-old Stone Burial Tombs
The World’s First Astronomy Telescopes?
The Guardian reported on June 29 that astronomer Fabio Silva from the University of Wales Trinity Saint David and the research team found that the 6,000-year-old burial tombs look to be positioned to spy out certain bright stars, such as Aldebaran, thus providing their ancient builders an astronomical telescope ...The telescope was made by the passageway providing a tube that blocked out other extraneous phenomena, allowing the viewer to see the targeted object.
Silva had the following to tell The Guardian“The key thing is that a passage grave with its long corridor acts like a telescope that does not have a lens – it is a long tube from which you are looking at the sky.” As Kieran Simcox, a student at Nottingham Trent University (and leader of the project), pointed out in the National Astronomy Meeting 2016 press release: “It is quite a surprise that no one has thoroughly investigated how, for example, the color of the night sky impacts on what can be seen with the naked eye.”
Another Article Stated:The findings were presented June 29 at the Royal Astronomical Society's (RAS) National Astronomy Meeting 2016 in Nottingham, in the United Kingdom. They were presented in a special session addressing how cultures and societies have been shaped by studying the sky, and vice versa.
And in another article:While a modern telescope works by magnifying images with mirrors or lenses, this ancient structure is a long, narrow corridor designed to filter out unwanted light. The corridor helps when viewing stars during the hours of dawn and twilight, when the light from the sun makes it hard to view stars near the horizon.The researchers believe that the Seven-Stone Antas corridor was used to view the star Aldebaran, the red giant in the constellation Taurus. Aldebaran first becomes visible in the Northern Hemisphere in the early morning of late April, just before sunrise, and viewing it through the passage could make it visible days earlier. Aldebaran likely was a seasonal marker, and its appearance would signal migration patterns or weather changes. 
And still another article: Researchers are focusing on the alignment of the stars with megalithic tombs—stone structures known as dolmens that feature long narrow entrances that act as apertures, essentially zooming in on stars and planets that wouldn’t always be visible from the outside.


This is of particular interest to me because on March 17, 2015 I wrote the following article for this blog DeconstructingTime:

Computing the Winter Solstice at Newgrange: 
Was Neolithic Science Equal To or Better
Than Ancient Greek or Roman Science?

This blog of mine has now been reprinted 
on the official Newgrange website in Ireland:

A shaft of light shining into the passageway at Newgrange in Ireland. 
Used with permission: photo by Anthony Murphy,

In this article I argued that the passageway at Newgrange was an instrument which was capable of accurately determining the day of the winter solstice in real time, something which the Greeks and Romans could not do 3,000 years later. See the following Wikipedia article:

There is a good deal of similarity between this idea and the theory that a 6,000 year old telescope was used to see a key star at it's earliest appearance around dawn or dusk. 

With both Neolithic structures the passageway was an astronomical instrument designed to enhance the view of the heavens to make a precise observation possible. For example, in the case of one Portuguese burial-tomb it is suggested that the passageway helped to determine the earliest heliacal rising of the star Aldebaran and in the case of Newgrange the passageway helped to determine the day of the winter solstice at sunrise.

With the prehistoric Portuguese telescope the idea was to block out some of the predawn sunlight with the walls of the tunnel/passageway to make the star Aldebaran visible in the brightening sky.

"The entrance creates an aperture as large as 10 degrees through which your naked-eye view is restricted," Daniel Brown, another research team member, explained. "This would allow enhanced observing, especially in the twilight hours of dusk and dawn." 

With the passage tomb at Newgrange I argued that the long passageway greatly magnified the movement of the sun's rays at dawn so that the actual day of the winter solstice could be determined with precision.  

"Sketch of a cross section of the Newgrange passage grave made by William Frederick Wakeman."
Quote from
Wakeman's Handbook of Irish Antiquities (1903). p. 85.

If we can view the Newgrange structure and winter solstice alignment as an instrument, then we can say the following:
Light at sunrise near the time of the solstice was at first restricted to a narrow beam that went down a narrow hallway where it spread out, but in a controlled manner. This 'device' was very much like a magnifier that could enlarge and exaggerate the movement of the sun at a time when detecting movement was particularly difficult. Everyday the angle of the light changed along the walls and floor, and the light advanced further or retreated.
It is, therefore, possible that Neolithic astronomers could have made a determination about the day of the solstice with the following data their instrument had gathered: the entry point of the light, the length of time the light shown, the angle and amount of the light on the walls and floor, the width of the light, the rate at which the beam of light widened and contracted and possibly the quality of the light and shadows on the deeply grooved triple spiral stone and other stone carvings. 


In any case both ideas can be tested. 

In the case of archaeologists studying the 6,000-year-old burial tombs in Portugal:
Astronomer Fabio Silva, from the University of Wales Trinity Saint David, told The Guardian, “We are going to simulate this star rising at twilight conditions and allow people to tell us when they can see it. Then [we will] compare that with a control group of people that are in a room which would replicate the conditions of being outside the passage grave.”
In the case of Newgrange I believe that with the help of archaeological laser scanning devices and CAD software the orientation and passageway at Newgrange could be accurately simulated along with the sunlight from the rising sun around the day of the winter solstice -- but taking into account the conditions when Newgrange was built 5,000 years ago. This should provide definite proof of the accuracy of the Newgrange passageway instrument. 
NOTE:To add an aside: While the passageways in the Portuguese burial tombs have been compared to telescopes to see a star more clearly, the passageway at Newgrange could be compared to a pinhole camera -- as it is designed to capture light from the sun.